1. Component Symbols & Information Prof. Dr. Moustafa M. Mohamed Vice Dean, Faculty of Allied Medical Science, Pharos University in Alexandria

2. Resistors Resistors – An electrical component that opposes or resists the flow of current. Values in Ohms (units of resistance) color coded or military specification coded. K = kilo = 10 3 M = mega = 10 6 m = milli = 10 -3

3. Resistors (cont.) Lead Styles Axial Radial I.C. (SIP and DIP) Surface Mount

4. Resistors (cont.) Types Carbon Composition – Fixed Carbon Film - Fixed Metal Film – Fixed Wire Wound – Fixed or variable

5. Resistors (cont.) Graphic Symbols Fixed – Zig Zag with 3 points on top and bottom, with 60º angle between zigs, 1/8 to 3/16” tall. Variable – Rotary, slide, tapped, switched Reference Designation = R Potentiomete r General – (Rotary, slide, tapped, switched) Rheostat –Used to control current flow.

6. Capacitors Capacitors – A component that stores electrical energy between conductive plates separated by a dielectric insulation material. Values in Farads (unit of storage) and working voltage lettered on the body. – μ = micro = 10 -6 – n = nano = 10 -9 – p = pico = 10 -12

7. Capacitors (cont.) Types Electrolytic – fixed – polarized Tantalum – fixed – polarized Paper – fixed – nonpolarized Mica – fixed – nonpolarized Ceramic – fixed – nonpolarized Air – variable - nonpolarized

8. Capacitors (cont.) Lead Styles Axial Radial Surface mount

9. Capacitors (cont.) Graphic Symbols Nonpolar fixed Variable Polar Fixed Reference Designation = C + Used for coupling /passing AC signals and filtering frequencies (tuning, crossovers) Used for storing energy in DC applications (power supplies, filters) Used for passing AC signals

10. Inductors Inductors – Component that stores electrical energy in the form of a magnetic field. Consists of a coil of wire wrapped around a core of air or magnetic material. Also known as – Induction coils, coils, or chokes Values in Henries (units of storage) color coded or lettered – m = milli = 10 -3

11. Inductors (cont.) Types Air Core – Fixed Iron Core – Fixed and Adjustable Ceramic Core – Fixed Toroidal Core - Fixed

12. Inductors (cont.) Lead Styles Wire Lead PC Mount Eye Terminal

13. Inductors (cont.) Graphic Symbols Preferred IronCeramic Adjustable Used in filtering and tuning circuits Reference Designation = L

14. Transformers Transformers – Two inductors constructed side by side with no electrical connection between them. Used to transform energy from one side of the device to the other. – Values in volts, amps, primary (input) and secondary (output), labeled on units

15. Transformers (cont.) Types Primary-Secondary Ratio – 1:1 isolation style – Step-up – Step-down – Centertapped – Multitapped – Air core – fixed output – Iron core Fixed output Adjustable outputs Multitapped outputs – Ceramic core– fixed output

16. Transformers (cont.) Lead Styles Wire Lead PC Mount Eye Terminal

17. Transformers (cont.) Graphic Symbols Air Core Iron Core Iron Adjustable Iron Multitapped Used for power supplies Reference Designation = T

18. Diodes Diodes – Semiconductor component that allows current to flow in only one direction. It is also used to regulate voltage and emit light. – Values rated in current flow and voltage threshold and recovery time.

19. Diodes (cont.) Types Rectifier Zener Tunnel LED LCD Laser Photosensitive Standard Part Numbers - 1NXX – 1NXXXX

20. Diodes (cont.) Lead Styles Axial Radial Stud Surface Mount

21. Diodes (cont.) Graphic Symbols Rectifier/Small signal Zener Tunnel LED Photosensitive Reference Designation –CR, LED, DS, PSD

22. Assignment State the functions of Capacitor and mention 3 different types of it.